A massive winter storm blanketed the Southeast with ice and snow Wednesday and turned up the East Coast on Thursday, shuttering businesses, disrupting travel, closing schools and knocking out power. The storm has been blamed for several deaths.

Indeed, extreme cold can be extremely unhealthy.

“We estimate that the number of annual deaths attributable to cold temperature is 27,940 or 1.3% of total deaths in the U.S.,” Olivier Deschenes, an economics professor at the University of California at Santa Barbara and Enrico Moretti, an economics professor at the University of California at Berkeley, found in a 2007 research paper. “This effect is even larger in low income areas.”

Extremely hot weather isn’t good for your health, either. But cold, which seems to exacerbate cardiovascular and respiratory diseases, has a longer-term impact. The elderly and poor are particularly vulnerable.

Cold weather also has an outsize effect on food budgets. Researchers including Jayanta Bhattacharya, a professor of medicine at Stanford University, found that poor parents eat less — and reduce their caloric intake — during cold weather shocks as heating bills rise.

“Our results suggest that poor American families with children face stark choices in cold weather,” the authors wrote in a 2002 study. “In particular, they increase home fuel expenditures at the cost of expenditures on food and nutritional wellbeing.”

Rich families spend even more to warm their homes, but they also buy more food.

Not all research is so dire.

“After a snow storm, an individual who is going to purchase a 4-wheel drive vehicle appears to be more motivated go to the dealership than buyers of non-4-wheel drive vehicles,” according to authors Meghan Busse, a management professor at Northwestern University, Devin Pope, a behavioral scientist at the University of Chicago, Jaren Pope, an economics professor at Brigham Young University, and Jorge Silva-Risso, a marketing professor at the University of California at Riverside.

Conversely, sales of convertibles aren’t so hot.

Parents, meanwhile, don’t have to worry that their kids are falling behind because of all the snow days.

Joshua Goodman, a public policy professor at Harvard University, said that schools appear to be prepared to deal with coordinated disruptions like snow days. Problems arise when bad weather hits and schools don’t cancel classes.

When schools are closed, all the students are off. But when some students are in classrooms and others are at home, teachers have to take more time getting everyone on the same page.

“These results are consistent with a model in which the central challenge of teaching is coordination of students,” Mr. Goodman said in the 2012 study.

To be sure, Mr. Goodman’s source data is from the Massachusetts Department of Education—a state that is perhaps more used to snow days than those in the South.